Ever since Puel and Sigwart introduced heart stenting in 1986, it has been the standard care for relieving coronary chest pains. But, as David Epstein of ProPublica wrote, there is an epidemic of unnecessary medical treatments – one of them being the installation of stents in patients with stable angina.

Stents supposedly soothe the suffering of patients with angina, and reduce the risk of a future heart attack that may be fatal.

However, many studies have concluded this is not necessary. A 2007 study showed that stable angina could be controlled with oral medication and stents did not help with a longer lifespan or reduce the risk of disease. On the contrary, an increased risk of heart attacks and strokes could be the side effect of stent procedures.

Placebo effect of stents larger than thought

Backing this up, a recent study done by Imperial College London discovered “no evidence from blinded, placebo-controlled randomised trials” that stents are more effective than medications for the same affected demographic.

The study tested the efficacy of stenting on heart patients on 200 patients who all had one blocked artery, with a chest pain that limited their daily activity – especially on exertion.

For six weeks, all the subjects were stabilised with anti-coagulants, blood pressure medications and pain relief for their chest pains. They were then randomly assigned to the procedure where only half received real stents while the other half underwent a fake procedure, in which only a catheter was threaded through without insertion of the stent.

Six weeks later, the patients were evaluated on a treadmill test. There was no significant difference in how much exercise both groups could do, neither was there a difference in how much chest pain was reported.

What the study shows “is that [stents] work and don’t cause more harm – but, are no more effective” than drugs in the short-term reduction of chest pain or improvement in exercise capacity, asserted Indu Poornima, Allegheny Health Network medical director of nuclear cardiology, who was not part of the study.

Similar to the 2007 study, this new evidence questions whether it is ‘necessary’ for the procedure to be done should the results indicate no significance.

“This is still an area of controversy. There are no studies that showed stents were better than medications in reducing mortality or heart attacks in patients who have stable coronary artery disease,” added Poornima.

Reducing “knee-jerk reaction” to treat heart blockages

Dr Steven Nissen, chairman of the Department of Cardiovascular Medicine at Cleveland Clinic, says there was a time when stenting was used habitually without pausing to assess their value as a medical therapy – a “knee-jerk reaction”.

“But that era is gradually disappearing. Prudent physicians counsel their patients about all of their options and give the best medication therapy possible. When you do that, the number of people who actually need to have a stent is fairly modest.” emphasised Dr Nissen.

A comprehensive evaluation must be done and in most cases, patients can be managed by starting with medications first. For patients who are unable to tolerate certain drugs, stents are particularly useful.

Dr Nissen also pointed out that the results are still debatable as the treadmill test that the researchers used to analyse the effect of the stents is “fairly subjective”.

“People may stop on the treadmill for a variety of reasons, not all of which have to do with whether they are experiencing chest pain,” said Nissen.

He also urged that the study be done with a bigger sample size in the future in order to really determine the efficacy of stenting in heart patients.

Enters the new-age ‘resorbable stents’ as an alternative

In recent years, however, there have been talks about ‘vanishing’ or resorbable stents (naturally dissolving stents).This means that the material used for the stents will disappear after a period of time.

In theory, this would mean that the complications associated with the traditional stents, such as hardening of the arteries, clots, inflammation and even restenosis (re-narrowing of the vessel) will be significantly reduced.

Certain establishments, especially in the United States, are already using this new-age stents – but, the outcome is still an ongoing discussion and observation. MIMS

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